Cell proliferation inhibitory and apoptosis-inducing properties of anacardic acid and lunasin in human breast cancer MDA-MB-231 cells

The combination of two or more chemopreventive agents is currently being used to achieve greater inhibitory effects on breast cancer cells. Anacardic acid and lunasin are two plant-derived compounds that have been associated with anti-carcinogenic properties. These compounds show inhibitory effects on cell proliferation and inducing properties of apoptosis in human breast cancer MDA-MB-231 cell line. Both lunasin and anacardic acid exert their effects through the modulation of expression of several genes involved in cell cycle, apoptosis and signal transduction. Their combination arrests the cell cycle in S-phase and induces apoptosis at higher levels than that observed when each compound is used individually. This combination also promotes the inhibition of ERBB2, AKT1, JUN and RAF1 signalling gene expression, whose up-regulation has been reported as responsible for breast cancer cells growth and resistance to apoptosis. Our results introduce these two compounds as a promising strategy to prevent/treat breast cancer.     

Effect of temperature,pH and film thickness on nisin release from antimicrobial whey protein isolate edible films

BACKGROUND: An active packaging film based on whey protein isolate (WPI) was developed by incorporating nisin to promote microbial food safety. The effect of temperature and pH on the release of nisin from edible films of different thickness was investigated. The film mechanical properties and inhibitory effect were also evaluated. RESULTS: Nisin release was significantly favoured by low pH, with the highest release after 24 h (1325 IU), which was not significantly affected by temperature (5 or 10 °C). Thickness significantly affected film elongation, with thicker films showing the highest elongation (54.3 ± 2.7%). Water vapour permeability (0.15 ± 0.4 g mm m^?2 kPa^?1 h^?1) and elastic modulus were not significantly affected by thickness. The highest nisin effective diffusivity (5.88 × 10^?14 m² s^?1) was obtained using a solution at pH 4, 112 µm film thickness and a temperature of 5 °C. More than four log cycles of Brochotrix thermosphacta were reduced from the surface of a ham sample after 8 days of incubation at 4 °C by the active WPI film containing 473 IU cm^?2 nisin. CONCLUSION: Nisin diffusivity from WPI edible films was favoured at lower pH and film thickness. This active packaging film may be used to preserve the quality and safety of meat products. Copyright © 2009 Society of Chemical Industry     

Antioxidant activity and genotoxic effect on HeLa cells of phenolic compounds from infusions of Quercus resinosa leaves

Water infusions of mature and fresh Quercus resinosa leaves were evaluated for antioxidant activity and genotoxic effects on HeLa cells. Native Mexicans used to drink Q. resinosa leaves tea as a refreshing beverage. The air dried leaves were pulverised and boiled in water, then their phenolic content and condensed tannins were determined. The chromatographic profile of 15 phenolic components in Quercus leaves infusions was also determined by HPLC. In vitro analysis of antioxidant capacity of leaves infusion extracts were performed by the DPPH method and the deoxyribose assay. The genotoxicity of Q. resinosa leaves extracts was evaluated on HeLa cells as well as its underlying mechanism by the single-cell electrophoresis assay (comet assay). Results show that fresh leaves infusions increase the oxidative process and other damage to DNA in transformed human cells. Fresh leaves from Q. resinosa may serve as a potential source of phenolics with anticancer activity.     

Updating the research on the chemopreventive and therapeutic role of the peptide lunasin

Chronic diseases have become the medical challenge of the 21st century because of their high incidence and mortality rates. Modulation of diet and lifestyle habits is considered as the best strategy for the prevention of these disorders. Health promoting benefits beyond their nutritional effects have been described for multiple dietary compounds. Among these compounds, the peptide lunasin is considered as one of the most promising. Naturally present in soybean, lunasin has been extensively studied in the last two decades because of its potential against chronic diseases such as cancer, cardiovascular and immunological disorders. The purpose of this article is to summarise the evidence on the presence of lunasin in soybean and derived foods, and its bioavailability once it is orally ingested. The protective and therapeutic effects of this peptide against cancer, oxidative stress, inflammation, and high cholesterol levels as well as the molecular mechanisms of action involved in these effects are also described in this review. © 2017 Society of Chemical Industry     

Effect of Nanoemulsified and Microencapsulated Mexican Oregano (Lippia graveolens Kunth) Essential Oil Coatings on Quality of Fresh Pork Meat

Fresh meat is a highly perishable food. This work aimed to evaluate the influence of Mexican oregano (Lippia graveolens Kunth) incorporated into active coatings (ACs) spread on fresh pork meat as free (FEO), nanoemulsified (NEO), and microencapsulated (MEO) essential oil (EO), on its microbiological, physicochemical and sensory properties during 15 d at 4 ± 1 °C. Thymol and γ‐terpinene were identified in the EO. In vitro effect of 2.85 mg EO/cm² was tested against Brochothrix thermosphacta, Micrococcus luteus, Lactobacillus plantarum, Pseudomonas fragi, and Salmonella Infantis. FEO antioxidant capacity (DPPH assay) was significantly higher than that of thymol, NEO and MEO (93.53%, 89.92%, 77.79%, and 78.50% inhibition, respectively), and similar to BHA (96.03%) and gallic acid (95.57%). FEO, NEO, and MEO ACs on meat caused growth inhibition of lactic acid bacteria (5 log population reduction) and Pseudomonas spp. (4 log reduction), whereas ≤1.5 log population reduction was observed for B. thermosphacta and Salmonella Infantis. Meat microbiota was more efficiently controlled by MEO than by FEO or NEO. ACs delayed lipid and oxymyoglobin oxidation of fresh pork meat. After 15 d of cold storage meat added with EO coatings was desirable for panelists, whereas untreated (UT) samples were undesirable. Active coatings are a significant alternative method for fresh meat preservation.     

High Hydrostatic Pressure and Temperature Applied to Preserve the Antioxidant Compounds of Mango Pulp (<Emphasis Type="Italic">Mangifera indica</Emphasis> L.)

High hydrostatic pressure (HHP) processes combined with moderate heating can be used to preserve foods while maintaining general quality. The effect of these conditions on the total phenolic (TP), vitamin C (L-ascorbic acid (AA)), carotenoids, and antioxidant activity (AOA) of mango purees was evaluated. Purees were processed at 400–550 MPa/34 and 59 °C at different holding times. Unprocessed puree had TP of 26.6 mg gallic acid/100 g, 21.1 mg L-ascorbic acid/100 g, AOA of 885 μmol trolox equivalents/100 g, and total carotenoids of 6.0 mg β-carotene/100 g. HHP treatments increased the phenolic concentrations up to 34% (550 MPa/59 °C/2 and 4 min) compared with the initial content, probably due to improvement of their extraction. AA content was reduced significantly (10–45%) after all HHP processes performed at 59 °C, while at 34 °C, they were diminished only after 8 and 16 min of treatment (13–26%). At 34 °C and lower times, AA concentration increased in average 18%. Total carotenoid retention in HHP-treated samples varies from 77 to 98%, being the higher the temperature the lower the retention observed. The concentration of most individual carotenoids remains unchanged, but violaxanthin content was reduced (21–26%) and 9-cis-violaxanthin was increased by about 10%. The AOA was also increased (up to 39%) at some processing conditions. A linear correlation between the TP and AOA was obtained. HHP at 550 MPa combined with moderate temperature (34 °C) at processing times up to 8 min is recommended for the maximum retention of the antioxidant compounds of mango puree.     

Degradation of tannic acid by cell-free extracts of Lactobacillus plantarum

The ability of Lactobacillus plantarum CECT 748^T to degrade hydrolysable tannins was evaluated. Three commercial tannic acids were incubated in presence of cell-free extracts containing soluble proteins from L. plantarum. By HPLC analyses, almost a complete tannic acid degradation was observed in the three samples assayed. By using HPLC-DAD/ESI-MS, we partially determined the composition of tannic acid from Quercus infectoria galls. This tannic acid is a gallotannin mainly composed of monomers to tetramers of gallic acid. We studied the mechanism of its degradation by L. plantarum. The results obtained in this work indicated that L. plantarum degrades gallotannins by depolymerisation of high molecular weight tannins and a reduction of low molecular weight tannins. Gallic acid and pyrogallol were detected as final metabolic intermediates. Due to the potential health beneficial effects, the ability to degrade tannic acid is an interesting property in this food lactic acid bacteria.